The present invention relates, in general, to a drive system, and more particularly to a set of modular elements for the construction of a drive system, including at least one main transmission, a motor unit, and a stepped sequence of subtransmissions mounted between the main transmission and the motor unit.
It is generally known to construct drive systems from transmissions and motors which are part of a modular kit, whereby the transmission may be composed of a main transmission and a subtransmission. Reference is made, for example, to an article in German publication VDI-Z, volume 114 (1972), No. 2, pages 122-129 and entitled "Stand und Entwicklungstendenzen bei der Konstruktion und Anwendung von Getriebemotoren" (State and Tendencies in Development Relating to the Construction and Application of Geared Motors). Although such a modular set allows construction of a great number of drive systems in a cost-efficient manner, the use of only relative few elements poses a problem when it comes to covering a wide range with respect to speed and torque.
German publication DE-OS 201 94 34 describes the combination of single transmissions in stretched arrangement, whereby a transmission is placed before a second transmission, i.e. to use two transmissions in series. Both transmissions typically include completely closed gear cases. Such an interconnection of separate single transmissions is cumbersome and expensive.